Government regulations and consumer preferences continue to require a reduction in the acceptable noise levels produced from the tires of passenger vehicles. One source of such noise is resonance within the air chamber enclosed by the innermost surface of the tire and the rim. One type of effort to reduce tire noise is damping the sound from the air vibration in the air chamber, which efforts have focused mainly on altering the innermost surface of the tire adjacent the tire carcass. Shortcomings in these previous efforts, as well as new stricter regulations regarding noise reduction, have provided a need for further improvements to the tire to reduce sound transmission due to vibrations within the air chamber.
Typically, carcasses of pneumatic green tires are built as a series of layers of flexible high modulus cords encased in a low modulus rubber wherein an innerliner is positioned to form the innermost surface of the tire. The green tire is cured in a curing press using a curing bladder, which forces expansion of the tire. During curing, the innerliner expands with the carcass, which is forced against the indentations in the curing mold to form the tread of the tire, and all components are co-cured so as to provide a substantially cohesive bond between one another.
U.S. Patent Application 2011/0308706 A1 discloses a method for making a pneumatic tire with a foam noise damper. According to this method a silicone rubber foam noise damper is adhered to the inner liner of a green tire and is covered with a barrier layer. After curing the barrier layer is removed to uncover the foam noise damper.
U.S. Patent Application 2003/0041942 A1 discloses another method of applying a noise damper to a pneumatic tire. In particular, an elastic band comprising one or more flaps is put around the wheel rim.
A challenge has been presented to provide a closed annular strip to a radially inward oriented surface of a tire.
A further challenge has been presented to provide a method of attaching an annular strip to a radially inward oriented surface which requires less manual steps.
A further challenge has been presented to provide an annular strip fitting an inner diameter of a tire.
Another challenge has been presented to apply an annular strip to a tire's innerliner which is reliable and repeatable with high quality in mass production.